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Steve Gottlieb
January 15th, 2013, 06:06 AM
I've updated my observing notes to the end of 2012 on Adventures in Deep Space (http://www.astronomy-mall.com/Adventures.In.Deep.Space). The link to the files is on the front page of the site, but here is the introduction...

Here are my observing notes for nearly 7200 NGC entries and an additional 785 IC entries. I began taking notes on the Messier objects with a 6" reflector in 1978 from northern California and by the end of 1981 was exploring fainter NGCs with a 13.1". The vast majority of my notes, though, were made using a 17.5" f/4.5 homemade dob (1987-2002) and an 18" f/4.3 Starmaster (2003-2011). Recent notes have been included with my current 24" f/3.7 Starstructure as well as a couple of hundred observations made with Jimi Lowrey's 48" f/4 from west Texas. Many of the NGCs have multiple observations made through two or more of these scopes.

As far as NGCs north of –40° declination, my notes are complete except for roughly three dozen objects – most of which are Milky Way star clouds or star asterisms. Observations of deep sky objects south of –45 degrees were generally made in Australia with 18" and 24" scopes during several week-long observing trips or in Costa Rica with a 13.1" scope.

Outside of the NGC itself, this is likely the most complete visual resource of NGC observations available anywhere. All of the entries have been checked for historical accuracy as part of the NGC/IC Project and many entries include historical background information.

Clear Skies
January 15th, 2013, 10:18 AM
That is an amazing resource for anyone ever gazing through a telescope. Observers worldwide will benefit from this! What's the total number of observations logged in your database?

As far as sharing of observations go, mine are available here (http://www.astro.clearskies.eu/webfiles/observations/all.xls) in Excel format, but only look at them if you feel like brushing up on your Dutch ;). I am in the process of translating all of it to English, hope to finish it before the end of the year... to many astroprojects running simulatenously! Total nr. of logged observations is about 6350, +/- 3400 for DSO's, +/- 2625 of which for NGC/IC (700 for carbon stars, 2250ish for double stars). Long way to go to complete all of the NGC & IC !

Preston Pendergraft
January 15th, 2013, 02:45 PM
Steve I enjoyed your posting about the eclipse. I am a little jealous at your 136 globular cluster talley! I am currently at 53 Milky Way globulars.... so I have quite a few left to go!

Ivan Maly
January 15th, 2013, 08:51 PM
Outside of the NGC itself, this is likely the most complete visual resource of NGC observations available anywhere.

Since the OP is modest, I will take it upon myself to point out that unlike the NGC itself (very much unlike the NGC itself!) this body of observations is uniform with respect to the chief variable in visual descriptions: the observer.

Steve Gottlieb
January 15th, 2013, 11:23 PM
That is an amazing resource for anyone ever gazing through a telescope. Observers worldwide will benefit from this! What's the total number of observations logged in your database?

I've collected notes on 12,350 DSOs (over a 34-year period) though many of these have numerous observations, so the total number is significantly higher.

Since much of the IC was discovered photographically (and goes as deep as 18.5 magnitude), I've never tackled the IC as an observing project but it might be possible to observe all the IC *visual* discoveries. There are 2763 such objects. Many were found by Lewis Swift using a 16-inch refractor in New York and California, Stephane Javelle with a 30-inch f/23 refractor at Nice, Guillaume Bigourdan with a 12-inch f/16 refractor at Paris, and by Barnard at Lick using 12-inch and 36-inch refractors.

Clear Skies
January 20th, 2013, 02:26 PM
Steve,

Reading through your observations I see quite a few descriptions including distances to nearby stars and such. I include the same "data" in my logged observations, but stick to a reference like "1/3 FoV towards ..." to describe a position or size. How do you get more detailed numbers in decimal arcminutes? An eyepiece, relatively high magnifications with a narrow FoV which would allow for easier sub-arcminute estimations?

Thanks,


Victor

Steve Gottlieb
January 20th, 2013, 06:13 PM
Hi Victor,

Galaxy sizes are just eyeball estimates at high power or estimated from a rough sketch with respect to nearby stars. I sometimes try to "calibrate" my eyeball at the start by looking at a couple of known double stars with separations of ~10", 20", 30" using say 300x, and then estimate sizes with the same mag.

But as far as distances to nearby stars and galaxies, the accurate decimal distances (5.7' NW, etc.), were measured later using Aladin or Megastar.

Clear Skies
January 20th, 2013, 06:50 PM
Allright, that's clear. I do the same thing after the actual observation using the AstroPlanner Field of View tab. Logged plenty of "bonus object" double stars by simply describing what I see in the FoV, recording that on my memorecorder, then verifying the description when working out the observation.